This invention relates generally to improvements in debris collection bags for use with automatic pool cleaning devices, particularly of the type designed for submerged travel along the floor and subsurface sidewalls of a swimming pool to collect and dislodge debris. More particularly, this invention relates to an improved debris collection bag designed for improved operating efficiency in the collection of relatively large debris, such as leaves, twigs, and the like.
Residential and commercial swimming pools conventionally include water filtration systems designed for removing dirt and debris from the pool water. Such filtration systems include a circulation pump for pumping pool water through a filter unit which separates dirt and other suspended debris from the water, after which the pool water is returned to the swimming pool. To maintain desired standards of water cleanliness and clarity, such filtration systems are normally required to be operated on a daily schedule for at least several hours each day.
While a swimming pool filtration system of the type described above is essential for maintaining water cleanliness and clarity, such filtration systems by themselves are generally unable to maintain the pool water is a satisfactory state of cleanliness over a long period of time. For example, a conventional water filtration system is designed to remove suspended water-entrained debris of a relatively small size and generally not for removing larger debris, such as leaves and the like, or othe particulate matter which tends to settle irrespective of size onto the floor and sidewalls of a pool. Accordingly, periodic cleaning of the pool floor and sidewalls by additional means is required to maintain the pool in a clean condition.
In recent years, a variety of in-the-pool cleaning devices have become popular for dislodging and collecting debris and sediment from the floor and sidewalls surfaces of a swimming pool. See, for example, the pool cleaning device shown and described in U.S. Pat. No. 3,822,754 which is adapted for submerged and generally random travel along the pool floor and sidewalls, wherein such devices are exemplified by the pool cleaner manufactured and sold by Polaris Vac-Sweep of San Marcos, Calif., under the trademark POLARIS VAC-SWEEP. Cleaning devices of this type are designed for connection to a supply of water under pressure, such as by connection to the discharge side of a filtration system circulation pump, and are driven hydraulically over submerged pool surfaces to dislodge sediment and further include hydraulic suction means for drawing sediment and debris through a suction mast into a porous collection or filter bag.
In general, collection/filter bags for pool cleaners have been formed from a meshlike material sewn into a shape having a lower open mouth for attachment about the upper end of the pool cleaner suction mast. Accordingly, water drawn upwardly into the bag filters through the meshlike material for return to the pool, whereas water-entrained debris larger than the mesh openings is trapped and collected within the bag. However, in previous collection/filter bags, the debris has tended to collect generally within or near the open mouth of the bag thereby obstructing water flow through the suction mast and inhibiting cleaner effectivity. This problem can be particularly severe when the pool cleaner is used to collect relatively large debris, such as leaves, twigs, and the like, which have fallen into the pool during windy or stormy weather conditions. Moreover, debris collected within the mouth region of the bag tends to fall back through the suction mast into the swimming pool upon cessation of cleaner operation. Still further, previous collection/filter bags generally have been shaped with a relatively tall and broad front profile to result in significant drag as the bag and cleaner move together through the pool water, wherein this drag can tip the cleaner to prevent the desired hydraulic suction operation, especially when collecting relatively heavy debris. In addition, when the collected debris is emptied from the bag, it has generally been necessary to remove the bag from the pool cleaner resulting in potential debris spillage into interfering contact with cleaner drive mechanisms.
There exists, therefore, a significant need for an improved debris collection bag for pool cleaners wherein the collection bag is designed for improved hydraulic operating characteristics particularly with respect to debris such as leaves and the like and for facilitated bag emptying without requiring bag removal from the pool cleaner.